Inexpensive Assistive Listening System

Ben Stiegler

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Aug 3, 2017
Location
Sf Bay Area
so I just did an indepth training on this, which I recommend highly. I thought I knew enough about loop systems ... wrong. Techniques for managing interference into adjacent spaces. Optimal angles to get even B-field strength across a space. Techniques for applying 90 phase shift to manage nulls. Escher-like topologies for better performance that go far beyond running a perimeter loop. It took 90 mins, plus there's a 15 item quiz to get level 1 certification. Even if you don't use or sell this brand, it was a very good training, and totally worth my time. Contacts to get the on-demand version of it:

Marketing & Training Coordinator - [email protected] 801.542.7771
Sales Engineering - [email protected] 801-542-7713
 

ACTSTech

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Joined
Nov 13, 2019
Location
USA
We're in the preliminary stages of renovations and this has come up several times, and the local installers can't seem to agree on how the system should be run, what the minimum number of devices should be, if we will need FM or if we can go bluetooth only...

The Listen equipment seems to be rather straightforward, so I think I could do the install and setup myself. I'm tempted to do the FM system and include a WiFi system in the proposal to future-proof (is there such a thing anymore?) the venue. Have you had a chance to do any work @Taniith with the shutdown?
 

FMEng

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Tacoma, WA
FM, IR, and current loop all have the the advantage of no latency. Bluetooth is limited in range and has a significant amount of latency. Wifi has more range, but also has latency. You'll never see a latency spec for wifi, because it varies so much.

In a remodel, where you can embed wire in the floor, current loop is probably the way to go. It has the advantage of working with many hearing aids, along with small receivers. The design of the loops has to be done right, or there will be dead zones or a noisy system.
 

ACTSTech

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Nov 13, 2019
Location
USA
In a remodel, where you can embed wire in the floor, current loop is probably the way to go.
Unfortunately, our renovation won’t allow for doing anything to the current floor. The fact that the proposed space is a 100+ year old former church makes it difficult to make major changes which is why the FM system makes the most sense.

And I understand the issue with latency and WiFi. I just was curious how it would work, and I like to tinker.
 

RonHebbard

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Joined
Jun 12, 2004
Location
Waterdown, ON, CA
Unfortunately, our renovation won’t allow for doing anything to the current floor. The fact that the proposed space is a 100+ year old former church makes it difficult to make major changes which is why the FM system makes the most sense.

And I understand the issue with latency and WiFi. I just was curious how it would work, and I like to tinker.
Have you considered a loop (or loops) on the ceiling of the floor below?
Think POSITIVE.
Test NEGATIVE.
Toodleoo!
Ron Hebbard
 

Ben Stiegler

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Joined
Aug 3, 2017
Location
Sf Bay Area
FM, IR, and current loop all have the the advantage of no latency. Bluetooth is limited in range and has a significant amount of latency. Wifi has more range, but also has latency. You'll never see a latency spec for wifi, because it varies so much.

In a remodel, where you can embed wire in the floor, current loop is probably the way to go. It has the advantage of working with many hearing aids, along with small receivers. The design of the loops has to be done right, or there will be dead zones or a noisy system.
take a certification course if you can - I learned so much from one re how to lay out the loops, placing nulls in constructive locations like the aisles, etc. Or get a designer who really knows what they are doing from the mfr - send pix and floor plans
 
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Ben Stiegler

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Aug 3, 2017
Location
Sf Bay Area
Have you considered a loop (or loops) on the ceiling of the floor below?
Think POSITIVE.
Test NEGATIVE.
Toodleoo!
Ron Hebbard
that's an interesting trick, Ron! Have you done that with wood? concrete? floors
 
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FMEng

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Fight Leukemia
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Location
Tacoma, WA
The church sounds old enough to have a wood floor with a crawl space or basement, which would work fine for current loops.

A member was pushing hard for current loops at our church. The floor is vinyl tile and carpet on cement. When I explained that it would require tape on the surface or floor replacement, that was the end of that. I might upgrade the FM system one of these days.
 

ACTSTech

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Joined
Nov 13, 2019
Location
USA
The church sounds old enough to have a wood floor with a crawl space or basement, which would work fine for current loops.

A member was pushing hard for current loops at our church. The floor is vinyl tile and carpet on cement. When I explained that it would require tape on the surface or floor replacement, that was the end of that. I might upgrade the FM system one of these days.
The Fellowship hall below the sanctuary would be ideal except for the fact that the ceiling is plaster and wire lath. When I've been working, I'll set up my bluetooth speaker and forget that it's playing through my phone. As soon as I go downstairs, the signal is gone (and believe me there's NO cell service almost anywhere in the church unless you get next to a window). Wireless router, same thing. I've tried placing the router in every imaginable location to penetrate the floor if it's upstairs or ceiling if it's downstairs. No go.

The floor isn't an option unless they decide to carpet over it, but the board is pushing for flexibility of the space meaning nothing permanent at the moment. I'm not sure taping wires to the floor, then having chairs set and reset, tables, dances, meetings, and so forth would be best. If they were placed, then the carpet installed over them, I'd worry about the eventual breakage. Thoughts?

Thanks as usual everyone!
 

LLDeen

Member
Joined
Jan 25, 2019
Location
Indiana
The floor isn't an option unless they decide to carpet over it, but the board is pushing for flexibility of the space meaning nothing permanent at the moment. I'm not sure taping wires to the floor, then having chairs set and reset, tables, dances, meetings, and so forth would be best. If they were placed, then the carpet installed over them, I'd worry about the eventual breakage. Thoughts?

Thanks as usual everyone!
1924 historic restored theatre here....our aisles are carpeted but underneath the seats is cement. Our loop system is ran in the carpet transition strips around each seating area. Has held strong for 10 years now. An option if carpet is decided on.
 

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
so I just did an indepth training on this, which I recommend highly. I thought I knew enough about loop systems ... wrong. Techniques for managing interference into adjacent spaces. Optimal angles to get even B-field strength across a space. Techniques for applying 90 phase shift to manage nulls. Escher-like topologies for better performance that go far beyond running a perimeter loop. It took 90 mins, plus there's a 15 item quiz to get level 1 certification. Even if you don't use or sell this brand, it was a very good training, and totally worth my time. Contacts to get the on-demand version of it:

Marketing & Training Coordinator - [email protected] 801.542.7771
Sales Engineering - [email protected] 801-542-7713
Ironically, when I reached out to Listen Technologies, they said they were moving away from the loop systems and concentrating on BlueTooth and WiFi instead.

As usual, I'm late to the party and missed the open bar...
 

MNicolai

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Location
Sarasota, FL
Ironically, when I reached out to Listen Technologies, they said they were moving away from the loop systems and concentrating on BlueTooth and WiFi instead.

As usual, I'm late to the party and missed the open bar...
Loop systems are harder to sell. Material cost isn't too high but lots of extra installation labor and more design labor -- much of which is supported by Listen -- and ultimately customers need to buy almost as many packs for a loop as they do for an FM/IR rig, so FM/IR rigs are still dominant in the market.

Conversely to how loop systems are designed/sold, you can sell BlueTooth and WiFi products to guided tours, interpreters, museums, and gyms all day long with minimal factory support required. I'm not surprised too surprised to see the shift. Though honestly I have yet to encounter any project myself where I could tolerate the kind of latency those systems have.
 
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ACTSTech

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Location
USA
For my project, I would like to investigate the WiFi not for people in the "auditorium" area, but more for the actors backstage and also for our downstairs area. I agree that the latency would be too great with WiFi only, but I know that more and more hearing aids have the built-in bluetooth. As long as the latency isn't too great, that would be fine for some of our crowd (they don't hear most of the production anyhow unfortunately) but not the ones that just want a boost.

In terms of latency on the board, the hall is around 100 feet deep, so I don't think I'd have to worry too much about putting delay in between the live actor mics and the hall mic, but I'll tinker. The FM system is how I think I'm going to go.
 

RonHebbard

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Premium Member
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Jun 12, 2004
Location
Waterdown, ON, CA
For my project, I would like to investigate the WiFi not for people in the "auditorium" area, but more for the actors backstage and also for our downstairs area. I agree that the latency would be too great with WiFi only, but I know that more and more hearing aids have the built-in bluetooth. As long as the latency isn't too great, that would be fine for some of our crowd (they don't hear most of the production anyhow unfortunately) but not the ones that just want a boost.

In terms of latency on the board, the hall is around 100 feet deep, so I don't think I'd have to worry too much about putting delay in between the live actor mics and the hall mic, but I'll tinker. The FM system is how I think I'm going to go.
Speaking of latency on the board, how's latency on your board of directors in terms of approving your plans and promptness of payment?
Think POSITIVE.
Test NEGATIVE.
Toodleoo!
Ron Hebbard
 

ACTSTech

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Joined
Nov 13, 2019
Location
USA
Speaking of latency on the board, how's latency on your board of directors in terms of approving your plans and promptness of payment?
Think POSITIVE.
Test NEGATIVE.
Toodleoo!
Ron Hebbard
If we were having a footrace of the minds with some of the board members, I'd time them with my calendar. My calendar only lasts a year though...

To be honest, we have the support. I asked for $1000 for upgrades that I NEED to make right now, and instead of asking for input, I told them what I needed and they gave me the go-ahead. I had to pull teeth, but without a stream of revenue I understand why they are hesitant. They tend to drag their feet when it's large amounts of money or if they all have ideas (like the ongoing moving light push), but things that I need, like repairs to in-wall microphone lines which were damaged (oh no! They won't be heard!) or new network lines (I'll have service so I can tweet how wonderful I am in the show!) they don't have issues. I suppose every board is like that.

I'm hopeful that they see the benefit of having this assistive listening system in place when we open the renovated venue. They're main push now is they want a place to put on their shows. It's not that they don't understand the scope of what we're doing, it's that they don't suspect it at all. I've spend countless hours trying to get them to be heard in other shows, they don't think about that. They want their microphone to work, they don't care how it works. We both have the same end goals, but we're coming from different directions. I'd like to have someone's elderly parents come and hear without and then with the ALD to see what they think, that would seal the deal.
 

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